Question

Rusting of iron is an example of:
(A) Reduction
(B) Ionisation
(C) Oxidation
(D) Dissociation

Answer 1

Hint: During the process of rusting of iron, iron combines with oxygen in the mere presence of water and moisture to form rust; reddish-brown in colour. The rust is actually the mixture of iron oxides together.

Complete answer:
Let us study the process of rusting in detail to answer the given illustration;
Rusting of iron is the prime type of corrosion process taking place in nature. It degrades the quality of iron. The process of rusting is the type of slow oxidation basically, where it takes much longer time to degrade.
The reaction of rusting involves an increase in the oxidation states of iron due to the loss of electrons. Rust is a non-toxic hazard to the environment thus, poses zero biological hazard.
Therefore, we can conclude that rusting is the oxidation process.

Hence, option (C) is correct.

Note:
Do note that rusting of iron is actually the redox reaction where the oxygen acts as oxidising agent to oxidise iron and simultaneously, metal iron also acts as reducing agent to reduce oxygen.
Also, rust is the mixture of two iron oxides which vary in their oxidation states with respect to iron. They are ferrous oxide or iron (II) oxide and ferric oxide or iron (III) oxide.
Also, rusting of iron can be considered as a combustion reaction in which very small amounts of heat is liberated.